Nucleosome model proposed by

Options

A. Du-Praw
B. Kornberg and Thomas
C. Sleffensen
D. Waldeyer and Taylor

Answer

To answer the question "Nucleosome model proposed by," we need to analyze the options provided and identify the correct one based on historical scientific contributions.

### Step-by-Step Solution:

1. **Understand the Question**: The question asks who proposed the nucleosome model, which is a fundamental concept in the structure of eukaryotic chromosomes.

2. **Review the Options**: The options given are:
- A. Dupro
- B. Conberg and Thomas
- C. Stephensons
- D. Weldair and Taylor

3. **Analyze Each Option**:
- **Weldair and Taylor**: Weldair is known for contributions to the neuron theory and chromosome naming, while Taylor is recognized for the semi-conservative model of DNA replication. Neither is associated with the nucleosome model.
- **Dupro**: He proposed the folded fiber model of chromatin but did not propose the nucleosome model.
- **Conberg and Thomas**: They are credited with the observation and proposal of the nucleosome model. Specifically, Roger Conberg played a significant role in defining the structure and existence of nucleosomes.

4. **Conclusion**: Based on the analysis, the correct answer is **B. Conberg and Thomas**. They proposed the nucleosome model, which describes how DNA is packaged in eukaryotic cells.

### Final Answer:
The nucleosome model was proposed by **Conberg and Thomas**.

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